Unable to Drop a REDOLOG Group ORA-00313 ORA-27037 No such file or directory

Cannot drop a standby redo logfile group because its files were already deleted on OS:

SQL> alter database drop standby logfile group 26;
alter database drop standby logfile group 26
*
ERROR at line 1:
ORA-00313: open failed for members of log group 26 of thread 2
ORA-00312: online log 26 thread 2: '/data01/awsdev2/datafiles/group_26.273.968987155'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
ORA-00312: online log 26 thread 2: '/data01/awsdev2/datafiles/group_26.273.968987153'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3

Fix:

Re-populate the logfile members inside this group:

SQL> alter database clear unarchived logfile group 26;

Database altered.

Now you can drop the standby redolog group:

SQL> alter database drop standby logfile group 26;

Database altered.